A woodland walk can calm our nerves, supercharge our memory and even help us sleep better. Cheryl Rickman gets to the root of why.
As William Wordsworth put it, trees can provide relief from “the fever of the world”. I find their strength, constancy and dependability comforting. It’s almost as if they whisper, “It’s okay. We are here.” But trees aren’t just a reassuring presence. Being around them can also improve our attention, help us sleep, speed up how we recover from stress and raise our cognitive ability – and it’s all down to science.
REBOOTING OUR NERVOUS SYSTEM
Trees produce a cocktail of botanical compounds, which soothe our autonomic nervous system. These compounds are a blend of essential oils called phytoncides and aromatic terpenes, which trees diffuse between each other to attract pollinators and protect themselves from bacteria, insects and fungi. Walking through woods, we breathe these in and absorb them through our pores. In response to this combination of phytoncide absorption and the soothing sights and sounds of the woodland, our nerves send electromagnetic signals to our brain – specifically to the hypothalamus – flicking the switch to shut down our “fight or flight” stress response and engaging the “rest and digest” calm response instead.
Switching off the stress response swaps cortisol and adrenalin production in our adrenal glands for happy hormones such as oxytocin and serotonin in our pituitary glands. Our breathing and heart rate slow, and stress and anxiety lessen. Our attention is restored. If we walk barefoot on the forest floor or sit beneath a tree and touch the earth, our bodies release even more feelgood chemicals. The bacteria found in soil – Mycobacterium vaccae – also activate the brain to produce serotonin, a neurotransmitter associated with happiness, calm and focus, and responsible for regulating mood, social behaviour and sleep. The effect of forest bathing (the Japanese practice of immersing yourself in the sights, sounds and smells of trees) on sleep is especially interesting and supported by research. In one study, forest health scientist Dr Qing Li and the Forest Therapy Study Group followed the sleep patterns of volunteers who undertook a 2.5km trail over two hours. The average sleep time of people in the group rose by an hour and 15 minutes (from just over six and a half hours to just under eight) on the night after the walk and 45 minutes on the one after that.
RESTORATIVE LANDSCAPES
Studies have also shown how much forests and parks, tree-lined streets and even images or videos of natural environments improve our emotional, cognitive and physical responses when we’re unwell or stressed.
In the 1980s, environmental psychologist Roger Ulrich conducted his “window view study” and found that patients treated in hospital rooms with a view of a tree or trees left hospital faster, had fewer negative evaluative comments in their nurses’ notes and took fewer strong analgesics than patients in rooms with a view of a wall.
In another study, Ulrich looked at whether a view of nature could help healthy volunteers recover from a stressful situation. After showing them intense videos of woodworking accidents, he measured their blood pressure, heart rates and sweat glands to determine their sympathetic nervous system activity (the system that controls our fight, flight or freeze response). Ulrich then asked half the group to watch a video of an urban scene and the other half to watch a video featuring a natural landscape with trees. The latter group returned to their baseline state within five minutes. The former group had only partially recovered after ten minutes.
FREEING UP OUR THOUGHTS
Trees also help us to focus. Spending even 20 minutes around them can boost our memory and concentration, catalyse creativity and open our mind to problem-solving. In a study led by researchers at the University of Michigan, people who walked around an arboretum performed 20 per cent better in a memory test the second time they took it compared to those retaking the test after strolling through the city, who showed no improvement.
And the more time we spend replacing tech with trees, the better. Four days of nature-immersion and a decrease in exposure to technology resulted in 50 per cent improvement in a creative problem-solving test, according to a study in the PLOS One journal.
In our regular life, where multiple demands compete for our attention, being around trees allows us to just be and to rest our befuddled brains. This enables us to engage in what environmental psychologist Rachel Kaplan calls “soft fascination”, where the landscape gently entices attention rather than demands it.
I love that gentle enticement of trees, that invitation to “Come, look, be still with us”. I always feel more reflective and more likely to daydream as I wander in the woods. Among trees, the sharp edges of life round off. Whether sheltered from the rain beneath their branches, leaning against their trunks supported by their strength or walking alongside them, the silent solace they provide gives me space to breathe in the sweet air of solitude, unfurl my thoughts and think things through. They give me permission to sit in silence, be myself and reboot.
EXTRACTED FROM Tree Glee: How & Why Trees Make Us Feel Better by Cheryl Rickman (Welbeck Balance, £16.99). Visit treeglee.co.uk to learn more.
Review
‘This lovely book is an absolute gem’ Joanna Lumley, Tree Aid Patron.
‘Trees are so important to our health and that of the planet. This inspirational book shows just how we can thrive together’ Alan Titchmarsh MBE
‘I have loved trees as long as I can remember, and Cheryl Rickman’s wonderful book illuminates the vitally important role they play, not only in maintaining the health of our planet and a habitat for so many living creatures, but also in providing us with mental and physical healing. Tree Glee also presents ideas on how you can help protect our amazing trees for the good of all’ Dr. Jane Goodall, DBE, Founder of the Jane Goodall Institute & UN Messenger of Peace
‘A blend of evocative nature writing, wellbeing advice and a call to action … This gorgeously illustrated book offers practical tips, exercises and thought-provoking reflections to help us engage with our natural habitat and become healthier and happier as a result’ The Lady
Tree Weaver 